<template>
<div>
<input type = " button" value =" +1" @ click=" addNum" />
{{num}}
<input type =" button" value=" -1" @ click=" subNum"/
</div>
</template>
<script>
export default{
    date(){
        return{num:0};
    },
    methods:{
        addNum(){
            this.num++;
        },
        subNum(){
            this.num--;
        },
    },
};
<script>
<style>
</style>